Two wave pulses, each of total mechanical energy \(E_0\) and identical symmetric shape, travel toward each other at speed \(v\) on a horizontal stretched string with uniform linear mass density and tension. In Case 1, both pulses are upright with transverse displacement in the \(+y\)-direction. In Case 2, one pulse is upright and the other is inverted with displacement in the \(-y\)-direction. At the exact instant the two pulses fully overlap, which of the following correctly describes the total kinetic energy \(K\) and total elastic potential energy \(U\) of the string system in each case?